The invention relates to a magnetic head for detecting magnetic fields representing information on a relatively movable magnetic registration medium the magnetic head, includes a substrate on which a number of juxtaposed elongated magneto-resistive elements are provided which are each incorporated in a magnetic circuit constituted by a magnetic yoke which is provided with pole faces for the purpose of co-operating with the registration medium. Each magneto-resistive element is provided on two oppositely located edge portions with contacts for connection to a measuring current source.
A multitrack magnetic head of this type is known from British Patent No. 2,064,849 The known magnetic head has a number of spatially separated transducer elements of the magneto-resistive type and a plane surface for magnetic flux coupling of the transducer elements with a magnetic medium. To this end a layerwise formed pattern defining a number of magneto-resistive elements is provided on a common substrate, whilst the magneto-resistive elements are connected to contact faces by means of connection conductors. The magneto-resistive elements co-operate with discrete magnetic layers of the pattern formed from a number of discrete magnetic layers for defining the transducer elements.
As is known from Philips Technical Review 37, pages 42-50, 1977, no. 2/3, the elongated magneto-resistive elements will preferably have such a magnetic anisotropy that the magnetically preferred direction coincides with the longitudinal axis of the magneto-resistive element. For the purpose of linearising the magnetic head one or more oblique conducting strips may be provided on one of the plane surfaces of the separate magneto-resistive elements, preferably at an angle of 45.degree. with the longitudinal axis of the magneto-resistive element. These strips function as equipotential strips so that the direction of the current in the magneto-resistive elements constitutes an angle with the magnetically preferred direction.
Magnetic heads of the type described above are suitable for use in devices for industrial application with magnetic discs, drums or tapes as well as in consumer electronics, such as digital and analogue audio recorders.
It has been found that the known multitrack magnetic head is less suitable for detecting magnetic media which are provided with a number of juxtaposed very narrow tracks. This is related to the fact that as the track width is smaller, the length of the magneto-resistive elements must also be taken to be smaller in connection with the track density, thus creating a more unfavourable length/width ratio regarding the magnetic shape anisotropy of the magneto-resistive elements. This means that instabilities in the magneto-resistive elements may be produced during operation of the magnetic head, with domain walls being displaced in an unpredictable way and with troublesome noise phenomena occurring.